1. Field of the Invention
This invention relates to providing a means of transforming any data which can be represented in a format of M.times.N individual datum, into an audible representation of these data. Each datum can have individually specified properties.
One application of this technique is to provide an audible representation of video data. Since these data can be readily assimilated by the brain, they can provide either an aid to the visually handicapped or they can provide supplementary visual information to normally sighted persons.
2. Discussion of Related Art
The problem of providing a source of sensory stimulation for sight impaired persons in an attempt to replace lost visual perception has been pursued for many years. One example of an attempt to solve the problem is the use of physical stimulators which are driven by an apparatus receiving visual stimuli. The physical stimulators can be placed on a certain area of the handicapped person's body and a pattern of stimulation is produced representative of the visual pattern which would ordinarily be seen.
Also, substantial work has been done in converting visual stimuli into an auditory display comprising patterns of sounds which the handicapped person can be taught to associate with certain visual stimuli. One example of such a device can be seen in U.S. Pat. No. 3,800,082, issued Mar. 26, 1974, to Fish. The Fish system provides an auditory display of two-dimensional patterns by use of a slow scan television camera for producing first and second voltages respectively indicative of the vertical and horizontal positions of the scan and a further voltage indicative of the intensity at each point of the scan and hence of the presence or absence of the pattern at that point. The vertical position of the scan is represented aurally by the frequency of the tone heard, the first voltage being used to control the frequency output of a VCO. The horizontal position of the scan is represented aurally by the interaural difference between two tones presented so that a point on the left side of a pattern is indicated by a relatively loud sound in the left ear. However, it is noted that a raster-type scan as used in Fish requires that the scanning time be of large duration in order to insure that the sound pattern range produced is within the audible frequency range of a human being.
U.S. Pat. No. 3,907,434, issued Sept. 23, 1975, to Coles, shows a sight system for producing binaural sound representative of the location of a visible object with respect to a listener, the system includes means for generating first and second time related signals of an audible frequency and a headset having two independently operable earphones which are connected to the signal generating means for reproducing sound in each of the earphones in response to each of the first and second signals, respectively. One apparent difficulty with the Coles invention is that the use of both ears is required to receive the visual stimulation. Accordingly, normal aural stimulation can no longer be received by the user.
U.S. Pat. No. 4,000,565, issued Jan. 4, 1977, to Overby et al, shows an apparatus for converting silent digital visual display characters into sequentially enunciated audible tones. The apparatus takes the output from a visual display, serially by character, and converts the serial characters into serially enunciated tone codes according to a given code format which is then reproduced through an output transducer so that the audible tones may be understood by the user. It should be understood that the Overby et al device does not attempt to simulate sight but merely provides a means for audible recognition and is thus limited in use.